The eco-efficiency evaluation in China's cement industry: A city-level study.

To implement strict environmental targets in China's cement industry into small regions, one should evaluate the city-level eco-efficiency that provides comprehensive instruction. This study establishes a plant-level database with 4000+ production lines located in 341 cities, calculates the energy consumption and CO2, SO2, NOx, and PM emissions, evaluates the eco-efficiency in each city via Slacks-based Measure, and verifies the spatial features of these indicators. Results show that the energy consumption and emissions of the industry are highly concentrated, with ~10 % of the land area contributing to 28.4 %-34.6 % of the total amounts in 2019. The average eco-efficiency value of the clinker calcination and cement grinding processes are 0.761 and 0.714, but the city clusters having low eco-efficiency values are inconsistent with the ones having large energy consumption and emission amounts. The results can contribute to the implementation of the targets such as carbon peaking and pollution cap in China's cement industry.